1. Field of the Invention
This invention relates to an automatic dishwasher comprising a wash tub supported above a floor to form a motor cavity in which a motor, pump, and related dishwashing components are located. In one aspect, the invention relates to a sound attenuator comprising a sound barrier and a sound absorber installed along the motor cavity for attenuating sound emanating from the motor cavity during dishwasher operation. In another aspect, the invention relates to a sound absorber installed along the motor cavity for absorbing sound emanating from the motor cavity.
2. Description of the Related Art
Automatic dishwashers are well known, especially those for use in household environments. A typical automatic dishwasher comprises a washing chamber or wash tub that is supported in a frame and installed under a countertop. The frame supports the wash tub above the floor so that a motor chamber is formed beneath the bottom of the wash tub and the floor. This motor chamber typically houses components such as a motor, a pump, water supply and drain lines, electrical supply lines, and the like. The motor chamber is typically closed after installation of the dishwasher by an access panel.
The operation of the components frequently generate noise that can migrate from the motor chamber, even with the access panel installed. Prior attempts to attenuate the sound include the use of fibrous insulation mounted to the rear of the access panel. However, even with the fibrous insulation, the noise can still be loud enough to interfere with other activities conducted nearby, such as mealtime conversation, telephone use, or listening to a radio or television. The fibrous insulation permits some sound to make it to the access panel and into the room by gaps around the access panel or causing the vibration of the access panel.
It is desirable to have an automatic dishwasher that has a sound attenuator that can effectively control the sound generated by components located in the motor chamber. Since previously sold dishwashers do not have any sound attenuation or have inadequate sound attenuation, it is highly desirable to have a sound attenuator that can be added during the manufacturing of new machines as well as being retrofitted to already manufactured and installed dishwashers.